Improvement in dredgers



UNITED STATES PATENT OFFICE.

ADOLF C. BOTH, OF PORTLAND, MAINE.

IMPROVEMENT IN DREDGERS.

Specification forming part of Letters Patent No. 138,227, dated April 29, 1873; application led March 3, 1873.

To all 'whom it may concern Be it known that I, ADOLF C. BOTH, of Portland, iu the county of Cumberland and State of Maine, have invented a new and useful Improvement in Dredging Machinery; and I do hereby declare that the following is a full, clear, and exact" description of the construction and operation of the same, reference being had to the accompanying drawing and to the letters of reference marked thereon.

'Ihe rst part of my invention relates to the combination of connecting rods or levers in such a manner that the said connecting-rods shall guide the dredging-buckets, so that they are capable of opening as wide as possible in order to cover a larger area of the material to be excavated, and so that the cutting-edges of the buckets shall follow a long flat curve, which is nearly straight on its deeper part, thus procuring not onlyT level bottom when in operation, but at the same time it will cut easier, and leave the outer circular sides of the buckets, when closed, free from contact with the cut thus made, so that the suction, which exists in the case of buckets that cut on a circle, will be entirely prevented. The latter part of my invention relates to the combination of gearing in such a manner as to increase the closing or cutting power of the buckets.

Figure I is a side elevation of the dredging apparatus embodying my invention, showing the same in a closed condition. Fig. II is a .s ide elevation of the dredging apparatus,

showing the same in an opened condition. Fig. III is a section of Fig. I on line marked A B, showing that part of the apparatus which is at left hand of said line A B.

To enable those skilled in the art to make and use my invention, I will now proceed to describe its construction and operation.

The buckets a a, which are of the usual form, are provided with two sets of hinges b b and c c, the former near the periphery, the latter near the centerof the buckets.` The buckets are hung by these hinges to one end of two sets of connecting-rods d d and c c. The other ends of the connecting-rods e c are pivoted on the stationary shaft n, and therefore the hinges b b of the buckets, when movany lateral motion of the said connecting-rods and buckets is prevented. The bucket, following the combined movement of the lower ends of the connecting-rods cl d and c c, (the former moving nearly in a horizontal, while the latter moves nearly in a vertical direction,) is guided so as to open to a great extent, and at the same time the cutting-edges of the buckets will describe flat curves .fr y a, which are nearly straight and horizontal at their .lower part. The curves x y e will, nearly through the whole duration of the cutting, form a tangent to the cutting-edges of the. buckets, thus greatly facilitating the cutting of hard material, as clay, Sto.

The apparatus is operated by two chains, t ands', as usual. t is used for closing the buckets, and acts upon a drum, t', which revolves loose on the shaft-a. This shaft a is secured solid to the frames h h, and is intended to form a stay for the lower part of the framing h h. Two gears, la la, fastened to the drum t', transmit the power by means of the gears Z Z to the shaft o, on which are keyedv two chain-wheels, m m. From these the power is transmitted by the chains r 1^ to the sliding shaft p. Two connecting-rods, fj, are connected at their upper ends with this shaft, and at their lower ends with the eyes b` b on the buckets, transferring the movement of the sliding shaft p to the buckets. By bringing the stra-in to bear upon thebridlechains s s s', fastened to the sliding shaft, the latter will move up, and consequently the buckets will open, and at the same time the chain t will wind up on the drum t, ready for the next closing operation. The intermediate shaft o is hung to the frame in such a manner and at such a distance from the center line of the apparatus that the chains r r will pull in a vertical direction on the sliding shaft, and 2. The combination of the gearsk k and l l avoid the side pressure of the sliding shaft and the intermediate shaft o, operating as and against its guides. for the purpose specified.

Having thus described my invention, its con- In testimony whereof I have hereunto signed i struction7 and operation, What I claim7 and demy name in the presence of two subscribing sire to secure by Letters Patent, is Witnesses.

l. The combination of the swinging` con- ADOLF C. BOTH. meeting-rods e e and d d and the guide seg- Witnesses:

.ment g, operating as and for the purpose spec GEO. THOM, ined. SoPHUs HAAGENSEN. 

